In raw benchmarks, the new Sandy Bridge MacBook Air models score far higher than last year's Core 2 Duo versions, with the entry level model scoring nearly twice as high in Geekbench. Even the higher end 2.13 GHz Core 2 Duo MacBook Air is no match for the new entry level Core i5, and is smoked by the new higher end Core i7 option, despite the Sandy Bridge chips being clocked far slower than the previous generation of Core 2 Duo chips.

The new MacBook Air Core i5 and i7 are "ultra low power" variants of the Sandy Bridge chips used in this year's line of MacBook Pros, so they're both far more efficient as not quite as capable; they're also clocked slower than their Pro sibling chips, ranging from 1.6 to 1.8 GHz rather than the 2.3 to 2.7 GHz dual core chips used in the 13 inch MacBook Pro, or the 2.0 to 2.3 GHz quad core chips used in the 15 and 17 inch machines.

Even so, the 1.7 GHz Core i5 MacBook Air benchmarks beat last year's 2.4 GHz Core i5 MacBook Pro, and the high end Core i7 dual core MacBook Air option runs nearly as fast as the latest quad core i5 MacBook Pro. The MacBook Air is officially no longer a tepid performer.

In addition to raw computing power, the Sandy Bridge architecture includes a number of specialized processing features that help boost real world performance, including an accelerated AVC (H.264) video encoder and decoder that jumps in to help both when creating your own movies, when playing back HD movies, and when making FaceTime video conferencing calls. Apple says the new MacBook Air performs up to 2.5 times faster than the previous generation (citing photo and video heavy apps).

Selecting from available options

The 11 inch base model 1.6 GHz Core i5 MacBook Air is a reasonably speedy mobile Mac at $999, although opting for the higher end 11 inch model for an extra $200 makes more sense, as it delivers not only twice as much storage but twice the RAM, something that you can't add later at any price.

The 13 inch model starts at $1299, but delivers a larger screen, 128GB SSD and 4GB standard, and includes an SD card slot along with a CPU bump to the 1.7 GHz Core i5. Opting for the 256GB SSD costs another $300, so depending on your needs for storage, you may want to live with the base 128GB SSD and make plans to upgrade in the future when you run out of space (and as SSD component prices continue to fall).

For extreme storage needs, Apple lists four options for external Thunderbolt RAID devices built by Promise, ranging from a $999 4 TB unit; a 4x2 TB or 6x1 TB unit for $1499; or a massive 12 TB (6x2 TB) system for $1999. Plugging in that kind of storage also requires a $49 Apple Thunderbolt cable.

Jumping to the fastest CPU option, the 1.8 GHz Core i7, costs an additional $150 on the 11 inch model or $100 for the 13 inch MacBook Air. That seems to be a very economical upgrade, given that the high end chip boosts its benchmarks into the realm of the currently shipping, entry level MacBook Pros (which continue to be significantly more expensive, although also offer better graphics, a higher quality screen, and several other built in options).

AppleCare costs $249 for three years of service and is usually a very good deal, but you can buy it anytime within the original warranty period. Apple also offers three HP printers in a bundle deal that knocks off $100 when purchased with a new Mac, resulting in the $100, $200, or $250 printers being free, $100 or $150 after rebate.

Performance overview: RAM and Battery

More RAM is critical to Mac OS X's performance, even if the SSD on the new MacBook Air seems to suffer less from virtual memory paging than a conventional hard drive does. For that reason, the 2GB limit on the entry level 11 inch MacBook Air models seems rather inadequate. While you can order the Air with 4GB of RAM installed, your only opportunity to do so comes at the time of purchase. There's no option to upgrade a RAM module later, as the memory chips are actually soldiered onto the logic board.

Compared to MacBook Pro models (which can accommodate 8GB of RAM), this lack of upgradability is a significant shortcoming, although not nearly as bad as the original MacBook Air, for which Apple offered no memory upgrade option at all beyond the standard 2GB. Unless you only plan to ever browse the web and do simple email and document editing, it makes a lot of sense to spring for the $100, 4GB upgrade at purchase. Note that doing so also limits your return options on what is now a "build to order" model, but that it will also increase the resale value of the machine. Thankfully, the entry-level $999 11 inch model is the only MacBook Air model Apple continues to offer with less than 4GB of RAM.

It does help that the Sandy Bridge architecture supports faster 1333MHz DDR3 RAM. However, some reports also indicate that Apple is using a variety of SSD components in the latest Air models, some of which do not benchmark as fast as previous models did. Unlike system RAM, the SSD units within the 2011 MacBook Air models are not soldered in, and can therefore theoretically be replaced with higher performance units after the fact.

Apple doesn't advertise which models will ship with which components, but existing reports indicate that new Air models ship with lower performing Toshiba SSDs, while previous MacBook Airs shipped with Samsung devices that benchmark with faster data throughput. In the units purchased by AppleInsider, we found a Samsung drive installed in one 11 inch model but a Toshiba drive installed in the 13 inch unit.

There does not appear to be any consistency in what brand of SSD is installed in a particular model, and of course Apple does not report the brand of the SSD that will be installed in a given machine configuration. It appears Apple has an internal baseline of SSD performance, and that some users will get devices that exceed that baseline. This has frequently been the case in earlier models, where Apple has used components from different suppliers.

The MacBook Air's integrated batteries not only last a long time, but combined with the instant standby and wake afforded by its SSD design, allow the machine to remain in standby for days; Apple says it can last for a month. This results in the new Air having a shelf life availability along the lines of the iPad, where you don't have to consciously think about keeping it charged up; just grab it and go.

It's pretty much always ready to play, and recharges rapidly when you do need to top off the battery. There isn't any external battery meter however, and the software-based reporting of how much charge you have left isn't always accurate.

Performance overview: Mac OS X Lion

The new Thunderbolt MacBook Airs boot the new Mac OS X Lion, and of course require the new release. This affords them a variety of iPad-like feature, from Full Screen Apps to Launchpad, to match their iPad-like hardware.

There's also deeper OS integration with Apple's online services, such as the new ability to reset your Mac's local password using your Apple ID (such as your iTunes, MobileMe and App Store account). Soon, Apple will also be rolling out iCloud services tied to the same Apple ID, enabling even greater integration between iOS and Mac OS X in terms of music, photos, documents, and third party app features.

Among the first things you'll notice after logging in for the first time is the Mac App Store recommending updates to the pre-installed iLife apps. Separately, you'll be notified of an update to iTunes via Software Update.

It's a little strange that some apps are updated through the App Store and others through Software Update, particularly iTunes, which isn't really a core part of Mac OS X and has historically been included in the iLife bundle. For now, you'll have to check both for updates on your installed apps. Below, iTunes asks to be updated via Software Update while other iLife app updates appear in the Mac App Store.

Any apps you've previously bought through the Mac App Store will show up on your new MacBook Air as available downloads in the Mac App Store's Purchases page, making it easy to install your apps without dealing with with DVDs (or using Migration Utility to do copy apps over). As a side bonus, the bundled iLife apps you get on your new notebook are tied to your Apple ID and therefore will show up as available downloads on other Macs you own, too.

Airs also leverage a feature of Mac OS X Lion providing a reinstallation partition, so they don't need to ship with a USB stick installer as the previous generation did. That's one less thing to lose, but don't worry that Apple is shaving 8GB of disk storage off the already limited capacity of your SSD. The recovery disk is just 650MB and a secondary partition storing a clean install of Mac OS X Lion is just 1.4GB, consuming a negligible portion of your total available storage.

Booting from the recovery disk (which you can do by booting with the Option key held down), you can access Disk Utilities, Terminal, Network Utility, and the Firmware Password Utility, as well as perform a clean reinstall of Mac OS X or restore the system from an earlier Time Machine backup. There's no DVDs or USB sticks to keep track of, and the utilities boot quickly because they're on the SSD. And speaking of SSD, Mac OS X Lion continues to provide support for TRIM features that help maintain the drive's performance over time.

One last mark left by Mac OS X Lion on the new MacBook Air models is the new configuration of keyboard icons. Replacing F3's Exposé and F4's Dashboard are new icons that bring up Mission Control (which is an enhanced Exposé integrated with Spaces, now presented by Apple as an unboxed icon of three boxes, launched by F3) and Launchpad (a Home-like screen of launchable apps, now designated by a grid of squares, and tied to F4).

The New MacBook Air in Review

The latest MacBook Air incorporates a variety of technologies sourced with both the simple, easy to use iPad and the high end MacBook Pro line. A combination of iPad-like speed, responsiveness and efficiency is mated with the high performance and flexible expansion options of the Thunderbolt MacBook Pros. This remakes the MacBook Air as a light, thin general purpose machine, rather than a subcompact riddled with various design compromises.

As noted last year, the overall design of the Air exemplifies the benefits of integrating customized parts together rather than just assembling stock components off the shelf. It's not just the SSD or the battery or the operating system that makes the Air a strong product, it's the combination and interaction between those parts. Few other manufacturers work so hard at tight integration and customization and take such forward thinking leaps when investing in the technologies needed to deliver these composite innovations.

The new MacBook Air models expand upon Apple's original intent to deliver a light, highly mobile notebook with full sized usability. The original Air debuted the company's innovative unibody construction, which Apple has since brought to the rest of its MacBook line. Unibody construction means that the shell is milled from a single slab of aluminum, rather than being pieced together by thin coverings screwed onto an internal metal framework.

This design gives the MacBook Air an incredibly thin and light but strong and rigid case, with improved port access. There are no doors or panels to flip up or break off, and there's less likely hood that the body will warp and creek as it ages and deals with wear and tear.

The smaller 11 inch Air delivers significantly better performance compared to the previous model while retaining the same compact form factor that should appeal to users who'd like an iPad sized device with the features of a full desktop operating system and a full, physical keyboard. Along with its 13 inch sibling, the new Thunderbolt Air delivers a significant jump in performance while still holding on to its impressive battery life delivered via integrated batteries.

Apple's bold move to standardize on SSD flash storage exclusively means the Air is virtually silent, faster than you'd expect given its processor clock speed, and jumps back from sleep as fast as the iPad. It can also coast along without a power brick in standby mode for days, a great feature when you're traveling and need every minute of battery life. The exclusive use of SSDs for storage and the removal of an optical drive means that the MacBook Air has virtually no moving parts to break outside of its cooling fans.

The new Thunderbolt Airs not only pack in a lot more performance and flexible expansion potential, but also reintroduce the a backlight keyboard that was dropped last year. While Thunderbolt provides a new option for plugging into FireWire and Gigabit Ethernet, only the 13 inch model provides an SD Card slot, leaving the 11 inch model continuing to require a USB cable to obtain the photos from your digital camera.

The skimpy 2GB of RAM on the base Air models begs for an upgrade, and many users won't realize they need more memory until they begin using it for some time, at which point it will be too late to add any. Of course, the Air isn't designed to serve as a powerhouse workhorse machine, so for users with greater need for mobility than maximum multitasking capabilities, the standard 2GB may be acceptable. However, it still seems likely that anyone who gets a 2GB Mac at this point is going to wish they'd splurged on an upgrade.

Unlike most PC notebooks, Apple's MacBook Air offerings don't include support for Blu-Ray nor provide a dedicated HDMI output connector, although the Air does support audio output through the Mini DisplayPort, meaning users only need a cheap dongle to route both HDMI video and high quality audio out through the Mini DisplayPort to an HDMI TV.

The new MacBook Airs began making their way to Apple stores and authorized over the past week, though Apple has yet to catch up with overall demand. Readers in the market for one of the notebooks can check out AppleInsider'sMac Pricing Guide (also below), where MacMall is already offering readers an additional 3% discount off its already reduced MacBook Air (and MacBook Pro) prices. The discount is instant when using the links below but available only when placing orders on line —you do not need to call MacMall to place a pre-order if the model you select is not currently in stock. The resellers are receiving new stock from Apple daily and new orders placed online will ship as soon as the reseller takes delivery of new stock.